Brand Name(s):

• Zovirax®Injection

Other Name(s):

• Acycloguanosine
• ACV

WHY is this medicine prescribed?

Your doctor has ordered acyclovir, an antiviral agent, to help treat your infection. The medication will be added to an intravenous fluid that will drip through a needle or catheter placed in your vein for at least 60 minutes every 8 hours for 5 to 10 days.

Acyclovir is used to treat

• herpes infections of the skin, nose, and mouth in people with weak immune systems
• herpes infections in newborn infants
• herpes simplex encephalitis (brain infection with swelling caused by the herpes virus)
• varicella-zoster (shingles; a rash that can occur in people who have had chickenpox in the past) in people with weak immune systems
• the first outbreak of a genital herpes infection (a herpes virus infection that causes sores to form around the genitals and rectum from time to time)

Acyclovir is in a class of antiviral medications known as synthetic nucleoside analogues. It works by stopping the spread of the herpes virus in the body. Acyclovir will not cure genital herpes and may not stop the spread of genital herpes to other people. This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

This medication is most effective if started soon after the first signs of infection appear.

Your symptoms should improve during your treatment with acyclovir. Call your doctor if your symptoms do not improve or if they get worse.

Your health care provider (doctor, nurse, or pharmacist) may measure the effectiveness and side effects of your treatment using laboratory tests and physical examinations. It is important to keep all appointments with your doctor and the laboratory. The length of treatment depends on how your infection and symptoms respond to the medication.

What SPECIAL PRECAUTIONS should I follow?

Before using acyclovir,

• tell your doctor and pharmacist if you are allergic to acyclovir, valacyclovir (Valtrex), or any other medications.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: amphotericin B (Fungizone); aminoglycoside antibiotics such as amikacin (Amikin), gentamicin (Garamycin), kanamycin (Kantrex), neomycin (Nes-RX, Neo-Fradin), paramomycin (Humatin), streptomycin, and tobramycin (Tobi, Nebcin); aspirin and other nonsteroidal anti-inflammatory medications such as ibuprofen (Advil, Motrin), and naproxen (Aleve, Naprosyn); cyclosporine (Neoral, Sandimmune); interferon; medications to treat HIV or AIDS such as zidovudine (Retrovir); methotrexate, pentamidine (NebuPent); probenecid (Benemid); sulfonamides such as sulfamethoxazole and trimethoprin (Bactrim); tacrolimus (Prograf); and vancomycin (Vancocin). Many other medications may also interact with acyclovir, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if there is a possibility that you may be dehydrated from a recent illness or activity, or if you have or have ever had problems with your immune system; human immunodeficiency virus infection (HIV); acquired immunodeficiency syndrome (AIDS); or kidney, liver, or nervous system disease.
• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking acyclovir, call your doctor.
• if you are using acyclovir to treat genital herpes, you should know that genital herpes can be spread through sexual contact even if you don't have blisters or other symptoms and possibly even if you are using acyclovir. Talk to your doctor about ways to stop the spread of genital herpes and about whether your partner(s) should receive treatment.
• be sure to drink plenty of fluids during your treatment with acyclovir.

HOW should this medicine be used?

Before you use acyclovir, look at the solution closely. It should be clear and free of floating material. Gently squeeze the bag or observe the solution container to make sure there are no leaks. Do not use the solution if it is discolored, if it contains particles, or if the bag or container leaks. Use a new solution, but show the damaged one to your health care provider.

It is important that you use your medication exactly as directed. Do not stop your therapy on your own or skip doses for any reason because your infection could worsen and result in hospitalization or could become more difficult to treat. Do not change your dosing schedule without talking to your health care provider. Your health care provider may tell you to stop your infusion if you have a mechanical problem (such as a blockage in the tubing, needle, or catheter). If you have to stop an infusion, call your health care provider immediately so your therapy can continue.

What SIDE EFFECTS can this medicine cause?

What should I know about STORAGE and DISPOSAL of this medication?

Your health care provider will probably tell you to store your medication at room temperature. Store your medication only as directed. Make sure you understand how to store your medication properly. Throw away any medication that is expired or no longer needed. Talk to your health care provider about the proper disposal of your medication.

Keep your supplies in a clean, dry place when you are not using them, and keep all medications and supplies out of reach of children. Your health care provider will tell you how to throw away used needles, syringes, tubing, and containers to avoid accidental injury.

What should I do in case of OVERDOSE?

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

Symptoms of overdose may include:

• agitation
• seizures
• extreme tiredness
• loss of consciousness
• swelling of the hands, feet, ankles, or lower legs
• decrease in urination

AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Last Reviewed: September 1, 2010.